1. TekScopes@groups.io

Re: TDS3044B repair

David Kuhn
 

" The problem turned out to be a bad solder joint on a surface mount choke
that supplied Vcc to the display."

Wow, congratulations! Good job! I could not tell you where to get case
components.

On Thu, Jan 2, 2020 at 12:23 PM Tom B <tbryan@nova.org> wrote:

Hello All,

I finally had time to get back to fixing the TDS3044B with no display.
The problem turned out to be a bad solder joint on a surface mount choke
that supplied Vcc to the display. The crack was so small it could
barely been seen on a microscope. So, the problem was not the display.
For those that need a display for a TDS3000B, the real part number is
NEC NL6448BC20-08E. The other thing that was helpful in troubleshooting
the display was a Hirose connector part number DF9A-31P. This gave me
some more room to probe the display connections on the main board. Now
I need to find the hub bits that hold the handle on the scope. If
someone knows where to get those please let me know.

Tom Bryan

On 11/7/2019 10:00 PM, Tom B wrote:
Hi Dave,

If you look at this video
https://urldefense.com/v3/__https://www.youtube.com/watch?v=Z_gvjmKHN4Y__;!b9GWhakWANQ!wEpfxjysOXjFgv3ZjJzwPT00sPf81J7-h9F-OyCNJMU1-f5Y3AG4Mbyun-yU$
it shows a part number on the back of the display as 65BLM04 and on
the front of the display the tag says NL6448BC20-08. If you search
each of these part numbers on ebay, the price is very different when
they are actually the same part. The cheapest price I could find for
the 65BLM05 is $158.74 (used), while the cheapest price for the
NL6448BC20-08 is $88 for a new part. These appear to be exactly the
same part. Any idea if there is any difference?

Tom

On 11/7/2019 2:28 PM, David Kuhn wrote:
https://urldefense.com/v3/__https://www.youtube.com/watch?time_continue=261&;v=iVU0YPIeovM__;!b9GWhakWANQ!wbXzExaWmEY10yA6ddr1j7dzMVPNV7j4iMLI9u6paEFuQ5tXhS6mqOV8S_HN$


https://urldefense.com/v3/__http://lcdparts.net/UBDetail.aspx?ProductID=3796__;!b9GWhakWANQ!wbXzExaWmEY10yA6ddr1j7dzMVPNV7j4iMLI9u6paEFuQ5tXhS6mqCtAAjYv$


Looks like a perfect solution for the NEC on the TDS3000 series and
in the
NEC 65BLM05 Display (virtually the same display as the one TEK uses)
in the
instruments I do a lot of work on.

Unlike the video, I would not remove the paper exposing the glue when
installing the strips. I don't want those LED strips permanently in my
LCDs in case they fail.

Dave

On Wed, Nov 6, 2019 at 11:40 PM Harvey White <madyn@dragonworks.info>
wrote:
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